SYSTEM
Accesses the system parameters to enable performing these tasks:
- Reading various cycle timing information and changing cycle timing
- Resetting timing counters
- Checking for and reading run-time errors
- Backing up, saving, and restoring variables
Arguments | ||
|---|---|---|
MODE | DINT | Identifies the command. |
ARG | DINT | Sets the cycle timing value when used with the SYS_TWRITE command. Enter 0 for
commands other than SYS_TWRITE. |
PARAM | DINT | The value returned by the command. |
These are the available commands (pre-defined keywords) and expected arguments for the SYSTEM operator:
Equivalent Defined Word for MODE | Definition | MODE (Command) | ARG | Param (Return Value) |
|---|---|---|---|---|
SYS_TALLOWED | reads allowed cycle timing | 1 | 0 | allowed cycle timing |
SYS_TCURRENT | reads current cycle timing | 2 | 0 | current cycle timing |
SYS_TMAXIMUM | reads maximum cycle timing | 3 | 0 | maximum detected timing |
SYS_TOVERFLOW | reads cycle timings overflows | 4 | 0 | number of timing overflows |
SYS_TWRITE | changes cycle timing | 5 | new cycle timing Ensure that the new cycle timing value combined with the
ISaGRAF Sleep Period value is less than the
Maximum Scan Time value. | new cycle timing |
SYS_TRESET | resets timing counters | 6 | 0 | 0 |
SYS_ERR_TEST | checks for run time errors | 16 | 0 | 0 if no error detected |
SYS_ERR_READ | reads oldest run time error | 17 | 0 | oldest error code |
Example
(* FBD example with "SYSTEM" operators *)
(* ST Equivalence: *)
alarm := (SYSTEM (SYS_TOVERFLOW, 0) <> 0); If (alarm) Then nb_err := nb_err + 1; rc := SYSTEM (SYS_TRESET, 0); End_If;
Provide Feedback